Your Corner Wrench: Are rusted bolts driving you nuts?

Rusty nuts and bolts can be a challenge to work with

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There are more than a few ways to defeat the evil monster that is rust

by
Brian Turner | February 28, 2017

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If you’ve ever done any maintenance or repairs to your vehicle (or any other mechanical device around the home), you’ve probably uttered more than a few choice words when struggling with a rusted and/or seized nut or bolt. But there are ways to defeat the evil rust monster and emerge victorious with knuckles intact and the swear jar empty.

There are basically four ways to tackle a rusted nut or bolt: cleaning, lubricating, heat and shock. All of these methods will help only if you have the correct wrench that properly fits the nut or bolt head. When selecting a socket for a seized nut or bolt, avoid 12-point types and stick to the six-point variety; they are much less likely to round off the head.

Cleaning rust off exposed threads will make things easier once you get things moving. More than one bolt has snapped after its nut started to loosen, only to get mired in corrosion farther down the threads. A small wire attachment on a hobbyist’s powered hand drive can get some severe cleaning power into the tightest spaces. For the less stocked tool kit, a small wire brush can do the same thing. For larger-diameter bolts, a battery terminal cleaner is also a handy way to remove rust without breaking the tool budget.

Lubrication is one of the favourite methods of freeing off rusted fasteners for DIYers and professionals alike, and the auto-parts store shelves are loaded with options. Stick with a foaming product such as Wynn’s Foam Spray (otherwise known as the “Nut Buster”). Sprays such as this tend to keep the lubricant adhered to the area where it’s needed rather than plain old penetrating oil or WD-40 which can run off and evaporate before doing their work. Patience is the key to this task and if possible it’s always a good idea to treat the bolts and nuts you need to remove the day before and let things soak in overnight.

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Taking a gas flame to try to remove a seized bolt or nut is probably the leading cause of fires in repair shops (backyard or professional types). It should only be attempted if the area involved is completely free of flammable materials or liquids and even then should be a last resort for the uninitiated. Fortunately there is a safe way of heating up metal without the use of a flame. Induction heaters are tools which convert electrical current to high frequency alternating magnetic fields. They operate on the principle of magnetic induction and will vibrate the electrons in the metal the tool tip contacts and this energy is dissipated by heat. While they can be expensive to purchase, they are available to rent from larger tool outlets. They have no effect on non-conductive materials such as glass, plastic or wood.

Before trying any of the above methods, you might want to simply use some accurately applied brute force. You’d be surprised what a simple rap on the head of a stubborn bolt with a hammer will do. It’s great for bolts that have their threads completely encased such as those used to mount various components. If you’re worried about damaging the bolt head to the point where a wrench won’t fit it, use a metal punch to concentrate the hammer blow on the centre of the head rather than its machined tool edges.